Running preamp in effects loop?

[Robin Ruscio]

I love my Aguilar Tone Hammer, it always goes in front of my bass to the amp.

I have a huge run of gigs coming up where I will be using both my fretted and fretless basses simultaneously through my two channel Epifani. I need to switch quickly between the two.

I want to have the Tone Hammer effect both basses. Can I put in the effects loop so that it works for both channels? Should I run the effects loop in series or parallel mode?

I know ideally I should run it before going to the amp at all, but i don't want to buy a second one as usually I don't have to do this.